Unless otherwise indicated herein, the description in this section is not prior art to the claims in this application and is not admitted to be prior art by inclusion in this section.
There has been known a typical light scanning device that includes imaging lenses layered in a plurality of stages at a bottom wall portion of a housing. This light scanning device includes a light source unit, which emits a plurality of light beams, and a deflection unit, which causes the plurality of the light beams emitted from the light source unit to be deflected to scan in the main-scanning direction. The plurality of the light beams deflected by the deflection unit pass through the imaging lens corresponding to the respective light beams to be imaged on a scan object surface.
There is proposed an example where imaging lenses are layered in the upper and lower stages.
Two imaging lenses have the same shape and three cylindrically-shaped bosses are formed at a bottom surface of the respective imaging lenses. Both sides of the respective bosses each include an adhesion portion constituted of an adhesive. Then, the lower-side imaging lens is secured to the bottom wall portion of the housing via the adhesion portion, while the upper-side imaging lens is secured to a top surface of the lower side imaging lens via the adhesion portion.